Nanoparticles (IMAGE) Johns Hopkins Medicine Caption These are T cells (red) and tumor cells (green) incubated with control particles (left) or immunoswitch particles (right). T cells that have latched on to tumor cells are indicated by green arrows. Credit Alyssa Kosmides, Johns Hopkins Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.